Notes:
- 1) The fitting includes the systematic errors.
- 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
- 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.
Time averaged spectrum fit using the average DRM
Power-law model
Time interval is from -14.200 sec. to 22.184 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.95746 ( -0.136902 0.133917 )
Norm@50keV : 2.24746E-03 ( -0.000183531 0.000180831 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.54 using 59 PHA bins.
# Reduced chi-squared = 0.9042 for 57 degrees of freedom
# Null hypothesis probability = 6.793818e-01
Photon flux (15-150 keV) in 36.38 sec: 0.330716 ( -0.023204 0.023257 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.52735e-07 ( -5.87777e-08 5.95391e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -14.200 sec. to 22.184 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.95818 ( -0.136956 0.135131 )
Epeak [keV] : 9999.36 ( )
Norm@50keV : 2.24711E-03 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 51.54 using 59 PHA bins.
# Reduced chi-squared = 0.9203 for 56 degrees of freedom
# Null hypothesis probability = 6.442980e-01
Photon flux (15-150 keV) in 36.38 sec: 0.330773 ( -0.024578 0.023193 ) ph/cm2/s
Energy fluence (15-150 keV) : 7.53084e-07 ( -6.35391e-08 5.84798e-08 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from 0.428 sec. to 1.428 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.98293 ( -0.272934 0.255271 )
Norm@50keV : 6.60011E-03 ( -0.00115607 0.00112023 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 63.33 using 59 PHA bins.
# Reduced chi-squared = 1.111 for 57 degrees of freedom
# Null hypothesis probability = 2.631113e-01
Photon flux (15-150 keV) in 1 sec: 0.982396 ( -0.13637 0.136444 ) ph/cm2/s
Energy fluence (15-150 keV) : 6.08247e-08 ( -9.92561e-09 1.0169e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from 0.428 sec. to 1.428 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.57675 ( -0.808686 1.21621 )
Epeak [keV] : 44.6045 ( )
Norm@50keV : 1.12373E-02 ( )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 62.86 using 59 PHA bins.
# Reduced chi-squared = 1.123 for 56 degrees of freedom
# Null hypothesis probability = 2.463216e-01
Photon flux (15-150 keV) in 1 sec: 0.966932 ( -0.141752 0.141558 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.8475e-08 ( -1.09327e-08 1.11684e-08 ) ergs/cm2
Time-resolved spectra
